Plug for dry wells.



J. G. ROBINSON.

PLUG FOR DRY WELLS.

APPLICATION FILED JULY l2. 19H.

.Patented Apr. 23, 1918.

BM I 1 JUN Gr. ROBINSON, OF TULSA, OKLAHOMA.

FLUG FOR DRY WELLS.

Specification of Letters Patent.

Patented flpr. 231, lll,

.hpplicatiorn tiled July 12, 1917. Serial No. 180,082.

To all whom t may concern:

Be it known that l, JOHN G. ROBINSON, a citizen of the United States, and a resident of rlulsa, in the county of lulsa and State of klahorna, have invented certain new and useful Improvements in Flugs for Dry `Wells, of which the following is a specification.

My invention is an improvement in plugs for dry wells, as for instance, oil or gas wells, to prevent salt water dowing from the said wells that might penetrate gas and oil sands, drowning production in adjacent wells, wherein the plug is so constructed that it may be shipped knocked down and assembled at the well.

ln the drawings:

Figure l is a sectional view of a well casing showing the plug as it is being lowered,

Fig. 2 is a similar view showing the plug lowered and tightened,

Figs.. 3 and 4 are enlarged sections on the lines 3-3 and 4-4 respectively ot Fig. 1, each view looking in the direction of the arrows adjacent to the line, j

Fig. 5 is a ersective view of the body of the plug with one of the wedge blocks detached.

rlhe present embodiment ot the invention is shown in connection with a well casing 1, and the improved plug comprises a frusto-pyramidal body portion 2 having upon each lace an under cut groove 3, the said grooves being at the centers of the faces.

rl`he body ol the plug is completed by wedge shaped blocks 4 and 5, each of which is provided on its inner face with an under cut longitudinally extending groove 6, adapted to register with the adjacent groove 3 of the body. ',l` he outer faces of the blocks are rounded as shown in Figs. 3 and 4, and the blocks 4 and 5 are so shaped that when they are in place on the body of the'plug, they will form with the block 2 a cylindrical body. The blocks 4 and 5 are locked to the block 2 by means ot keys 7, each ol the said keys being shaped to fit the registering ooves 3 and 6 and to lill the same, and to thus lock the blocks 4 and 5 to the block 1. rll`he blocks 4 and 5 are arranged with their large ends upward, while the block 2 is arranged with its large end downward, and a shoe 8 ol cast iron or like suitable material is secured to the bottom of the block l by a et screw 9. 'lhe shoe 8 has a reduced portion 10 at its upper la ol :am the same size as the bottom of the block 1, and in its under face is a central threaded'opening 11. rIhis opening 11 is engaged by the threaded upper end of a section 12 of pipe which has at its lower end a shoe 13 for engaging the bottom of the well in the manner shown in Fig. 2.

A substantially rectangular trame 14 of lead is connected with the upper ends of the blocks 4 and 5, and the opening through the frame is of suliicient size to receive the small end of the block l for some little distance below the said small end. A11 eye 15 is connected with the small end of the block 1, and this eye is adapted for attachment with a hoisting cable 16 for lowering the plug.

ln operation, the plug is assembled on the derrick floor by placing first the sides 4 and 5. rl`he locking keys 7 are placed in the grooves of the block 1, after which the blocks 4 and 5 are placed. The shoe 8 is connected with the bottom ot the block 1 and the :trame 14 with the tops of the blocks 4 and 5. The hoisting cable is connected with the eye 15 and the plug is ready to be lowered into the well after the pipe 12 has been laced. 'lhe length ot this pipe 12 depen s upon the point in the well at which it is desired to place the plug. lf for instance, the plug is to be ten feet above the bottom, a ten foot section of pipe is used.

After the plug has been lowered into the well until the shoe 13 strikes the bottom, the blocks 4 and 5 may be forced downward with respect to the block 1, as shown in Fig.' 3, until the plug is tightly wedged in the casing. 'l` he body of the plug is of soft wood, as for instance cypress, while the keys 7 are of hard wood. No nails or other metals are used in the connection ol' the plug.

The frame 14 is connected to the blocks 4 by means of straps indicated at 17, the said 'straps being countersunk in the blocks.

l claim:

1. A device of the character specified, comprising a plulg composed of a central frustopyranndal b ock and wedge-shaped blocks fitting the outer tace ofl the pyramidal block, and forming therewith acylindrical body, said first and la'st named blocks having on their adjacent faces, registering under cut grooves, keys engaging the registering grooves to lock the blocks together, a spacing member connected with the central block at the bottom thereof, and means con neeted with the upper ends of the wedgeshaped blocks for permitting them to be moved downward in unison, for the purpose specified.

2. A device of the character specified, 5 comprising a body composed of a central frusto-pyramidal block and Wedge shaped blocks fitting the outer face of the pyramidal block and forming with the said block a cylindrical body, said first and last named 10 blocks having on their adjacent faces registering under cut grooves, and keys engaging the registering grooves to lock the blocks together, a metallic shoe on the bottom of the central block and having a central threaded opening, a pipe threaded into the 15 opening and having a shoe at its other end for engaging the bottom of the Well, a lead frame connected with the upper ends of the outer blocks, and a hook connected with the upper end of the central block and eXtend- 20 ing through the frame.

JOHN G. ROBINSON. 

